<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .blue {
            background-color: lightskyblue;
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        .green {
            background-color: lightgreen;
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    </style>
    <script>
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</head>
<body onload="changeTrColor()">
<table border="1" cellpadding="0" cellspacing="0" width="30%">
    <tr>
        <th>ID</th>
        <th>姓名</th>
        <th>专业</th>
    </tr>
    <tr>
        <td>20180201</td>
        <td>刘备</td>
        <td>全栈</td>
    </tr>
    <tr>
        <td>20180202</td>
        <td>曹操</td>
        <td>java</td>
    </tr>
    <tr>
        <td>20180203</td>
        <td>孙权</td>
        <td>Python</td>
    </tr>
    <tr>
        <td>20180204</td>
        <td>刘表</td>
        <td>大数据</td>
    </tr>
</table>
</body>
</html>